Prognostic significance of microRNA-135 in patients with digestive system cancers: a systematic review and meta-analysis

The Role of microRNAs in Hepatocellular Cancer: A Narrative Review Focused on Tumor Microenvironment and Drug Resistance

Globally, hepatic cancer ranks fourth in terms of cancer-related mortality and is the sixth most frequent kind of cancer. Around 80% of liver cancers are hepatocellular carcinomas (HCC), which are the leading cause of cancer death. It is well known that HCC may develop resistance to the available chemotherapy treatments very fast. One of the biggest obstacles in providing cancer patients with appropriate care is drug resistance. According to reports, more than 90% of cancer-specific fatalities are caused by treatment resistance. By binding to the 3'-untranslated region of target messenger RNAs (mRNAs), microRNAs (miRNAs), a group of noncoding RNAs which are around 17 to 25 nucleotides long, regulate target gene expression. Moreover, they play role in the control of signaling pathways, cell proliferation, and cell death. As a result, miRNAs play an important role in the microenvironment of HCC by changing immune phenotypes, hypoxic conditions, and acidification, as well as angiogenesis and extracellular matrix components. Moreover, changes in miRNA levels in HCC can effectively resist cancer cells to chemotherapy by affecting various cellular processes such as autophagy, apoptosis, and membrane transporter activity. In the current work, we narratively reviewed the role of miRNAs in HCC, with a special focus on tumor microenvironment and drug resistance.

A review on the importance of miRNA-135 in human diseases

MicroRNA-135 (miR-135) is a microRNA which is involved in the pathoetiology of several neoplastic and non-neoplastic conditions. Both tumor suppressor and oncogenic roles have been reported for this miRNA. Studies in prostate, renal, gallbladder and nasopharyngeal cancers as well as glioma have shown down-regulation of miR-135 in cancerous tissues compared with controls. These studies have also shown the impact of miR-135 down-regulation on enhancement of cell proliferation and aggressive behavior. Meanwhile, miR-135 has been shown to be up-regulated in bladder, oral, colorectal and liver cancers. Studies in breast, gastric, lung and pancreatic cancers as well as head and neck squamous cell carcinoma have reported dual roles for miR-135. Dysregulation of miR-135 has also been noted in various non-neoplastic conditions such as Alzheimer’s disease, atherosclerosis, depression, diabetes, Parkinson, pulmonary arterial hypertension, nephrotic syndrome, endometriosis, epilepsy and allergic conditions. In the current review, we summarize the role of miR-135 in the carcinogenesis as well as development of other disorders.

Clinical value of miR-135 and miR-20a combined with multi-detector computed tomography in the diagnosis of gastric cancer

Background

To study the clinical value of miR-135 and miR-20a combined with multi-detector computed tomography (MDCT) in the diagnosis of gastric cancer (GC).

Method

A total of 146 patients with GC admitted to our hospital from January 2017 to June 2019 were selected and enrolled in the GC group. Another 103 patients with gastritis received in the same period were selected for the non-GC group. Besides, 95 healthy subjects who received physical examination in our hospital were selected into the healthy control group. Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression of serum miR-135 and miR-20a for each group. MDCT was used for detecting the clinical staging map of the enrolled patients. Pearson’s correlation analysis was used to analyze the correlation between serum miR-135 and miR-20a in patients with GC. The receiver operating characteristic (ROC) curve was drawn to analyze value of miR-135 and miR-20a in the diagnosis of GC.

Results

Compared with non-GC group and healthy control group, the levels of serum miR-135 and miR-20a increased significantly in the GC group, while no significant difference was found between non-GC group and healthy control group (P > 0.05). Analysis of the relationship with clinical characteristics showed that the expression of serum miR-135 and miR-20a in the GC group was significantly correlated with the progression of GC, TNM stage, degrees of differentiation, status of lymph node metastasis, and distant metastasis (P < 0.01). Pearson’s correlation analysis results showed positive correlations between miR-135 and miR-20a (r = 0.634, P = 0.000). The ROC analysis results showed that the optimal diagnostic values of miR-135 and miR-20a for GC were 7.56 and 5.82 respectively. The area under the curve (AUC) was 0.873 and 0.793 respectively. The 95% confidence interval (CI) was 0.811-0.935 and 0.697-0.890 respectively. The sensitivity and specificity of miR-135 and miR-20a combined with MDCT in the diagnosis of GC were 90.41% and 93.20% respectively. The sensitivity of combined use was significantly higher than that of single detection (P < 0.01).

Conclusion

There are high expression levels of serum miR-135 and miR-20a in patients with GC. A combined detection of miR-135 and miR-20a with MDCT can improve the diagnostic sensitivity of GC and improve the accuracy of the final diagnosis. Therefore, multiple combined detection is valuable in the diagnosis of GC.